Experfiment 1 Prelaboratory Assignment PDF

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Pre lab Experiment for Experiment 1 . From the textbook...

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Experiment 1 Pre laboratory Assignment Basic Laboratory Operations Date: ____9/5/2021_________ Name: ___ISIOMA NWANSOH _____

1 A proper fuel-air mixture is most critical in the production of an efficient, nonluminous flame. For the ignition of an efficient Bunsen flame in the laboratory, identify the most common fuel and the required air component.

Natural gas Oxygen is required. CH4 : Methane

2a. What is the dominant color of a nonluminous flame from a Bunsen burner? Explain

Blue, because methane burns blue when enough oxygen is supplied.

b. Is the temperature of a luminous flame greater or less than that of a nonluminous flame? Explain.

The temperature is less than that of a nonluminous flame. This is due to more oxygen being available for combustion.

3 Diagram the cross section of a graduated cylinder, illustrating how to read the meniscus. See attachment for diagram.

4 Experimental Procedure, Part B. What is the sensitivity of the least sensitive balance most likely to be in your laboratory? Top loading balance

Sensitivity +- 0.1 or +- 0.001.

5. A woodfire in a fireplace typically has a yellow flame whereas a (natural) gas fire (for a kitchen stove) is typically blue. Explain why the appearance of the wood flame is yellow whereas the gas flame most often appears blue

A wood flame has a yellow color due to inadequate supply of oxygen and the stove provides the flame with enough oxygen and hence the flame appears blue.

6. Refer to Technique 16B a Remove the drop suspended from a pipet tip by …...

By touching it to the wall of the waste beaker.

b. The finger used to control the delivery of liquid from a pipet is the ….

Index finger.

c. What should be done with the last bit of liquid remaining in the pipet after delivery? Dispose the liquid in the “waste “liquid container.

d. Most pipets are calibrated as TD 20°C. Define TD; what is its meaning regarding the volume of a liquid a pipet delivers? TD means tube delivery; it means that the pipet is created for the specific volume

7. Experimental Procedure, Part C.1. The density of diamonds is 3.51g/cm^3, and the density of platinum is 21.43g/cm^3. If equal masses of diamond and platinum are transferred to equal volumes of water in separate graduated cylinders, which graduated cylinder would have the greatest volume changes? Explain or show with a sample calculation.

Since the two samples have the same mass, the one with a lower density will displace the most water. In this instance, that substance is diamond 8. Experimental Procedure, Part C.3. The mass of a beaker is 5.333g. After 5.00mL of a concentrated hydrochloric acid solution is pipetted into the beaker, the combined mass of the beaker and the hydrochloric acid sample 11.229g. From the data, which is the measured density of the hydrochloric acid solution? D= M/V Combined mass = 11.229g Mass of the hydrochloric acid solution = 11.229g – 5.333g = 5.896g Density = 5.896/ 5.00 mL = 1.1792 = 1.1792g/cm...